Control device for rolled material feed

ABSTRACT

A device for controlling the feeding of rolled material is described. A roll of material is placed upon a rotatable spindle and pulled through a utilization mechanism by take-up roll which is actuated by a motor in known fashion. The invention includes a camming mechanism which applies and relieves tension to the supply roll to thereby control the rotation of the material supply and prevent backlash. Also included is a switching mechanism which automatically stops the motion of the take-up roll when the material supply is exhausted or when the material jams.

United States Patent 1191 Moss et al.

J [in 3,885,747 [451 May 21,1915

[ CONTROL DEVICE FOR ROLLED MATERIAL FEED [75] Inventors: James R.Moss,Mount Clemens;

Walter Wilsom'Northville, both of 'Mi'ch." I [73] Assignee: The Bendlx'Corporatlon,Southfieid,

' Mich. 221 'Filed: Mar. 28,1974

211 Appl. No.: 455,753

521 user .....142/7543242/1'90 511 int. Cl 3 51 25 22 [58] Field of Search 242/75.4, ,;7$,'l89, l90, d 242/674 [56] References Cited I UNITED STATES PATENTS 3,398,9l4 8/1968 Cunningham 242/75.43

3,539,129 l0/l970 Schmidt et al 242/189 3,545,694 12/1970 Ehrat ..242/67.4

Primqry Examiner-Leonard D. Christian Attorney, Agent, or Firm-Lester L. Hallacher I 57 1 5 ABSTRACT A device for controlling the feeding of rolled material is described. A roll of material is placed upon a rotatable spindle and pulled through a utilization mechanism by takeup rollwhich is actuated by a motor in known fashion. The; invention includes acamming mechanism iwhichapplies and relieves tension to the supplyfroll-to .therebycontrol the rotation of the 'material supply -an' d1prevent backlash. Also included is a switching mechanism which automatically stops the .motion of-the takerup, roll when the material supply is exhausted or when the material jams.

' Z'Claim's, 2 Drawing Figures CONTROL DEVICE FOR ROLLED MATERIAL FEED BACKGROUND OF THE INVENTION Various types of mechanisms utilize rolled sheet material in which the store of material is placed upon a supply roller and pulled through the mechanism onto a take-up roll. Such mechanisms include, for example.

primers for bar coded oralphanumeric labels in which the material to be printed uponis pulled into the vicinity of the printing mechanism. In many-instances cat bon paper must be pulled through the'mechanism simultaneously with the material. Various forms'of rolled sheet metal are also utilized in a similar manner. In all such mechanisms it is necessary to control the supply of material so that the material doesflnot-unwind or backlash when the'pullin g force is removed.'lt isalso necessary to deenergize the pulling device when-the supply of material is exhausted or the pulled material jams so that the pulling device does-not continue to' apply tension to the material and either tear the material or damage the printing .mechanisml The require- SUMMARY OF THE INVENTION The invention is directed to a simple and economical mechanism for applying tension to a roll of thin stock, such as paper. to permit smooth unwinding and to avoid backlash when the pulling force is removed. The invention also is responsive to the tension of'the unrolling material so that excessive tension created by jamming of the material will automatically stop the system. The invention also is responsive to the supply of material so that the system isautomatically turned off when the material supply is exhausted.

The invention includes a pivotable lever upon which is mounted a cumming mechanism. The camming mechanism is positioned in the proximity of a follower arm which carries a detent. The follower rotates about a rotatable member upon which a belt is mounted. The belt also extends over the roller which supports the material supply. Accordingly. rotation of the follower in response to the movement of the cam causes the detent to be biased against the belt. thereby increasing the force between the material supply and'the supporting roller. Accordingly, movement of the lever in response to a pulling force decreases the force and the material feeds freely. Removal of the pulling force increases the force to prohibit backlash which ordinarily would occur when the unwinding force is removed.

Also coupled to the lever in the proximity of the camming mechanism is a switching plate. Mounted in the proximity ofthe switching plate is a microswitch having a follower arm. The switching plate is configured so that the follower arm of the microswitch slides along the switching plate. The other end of the lever is provided with an idler wheel over which the material passes on the way to the take-up roll. Accordingly, tension in the material because of being pulled through the utilization mechanism causes the lever to rotate'about a pivot point located in the proximity of the cam. When invention.

all forces are permissible. the follower arm of the microswitch rides on the switching plate so that the switch is closed. However. undue tension on the material causes rotation of the lever and the follower arm of the microswitch rides upon a land of the switching plate.

- thereby affecting opening of the microswitch to demergize the pulling device.

The lever is biased to rotate in a direction opposite from the pulling direction of the material. Accordingly, the material being fed from the roller prevents the lever from rotating beyond .a'predetermined extent. When the material supply is exhausted, the lever rotates beyond this predetermined extent causing the follower arm of the microswitch to ride upon a different land of the switching plate. thereby affecting the opening of the switch to stop the take-up motor.

, CROSS REFERENCE TO RELATED APPLICATIONS The invention can be utilized in the printing mechanisrn described in application Ser. No. 418,722 filed by James R. MossonNov. 23,1973 now U.S. Pat. No.

3,848,257 and assigned to the assignee of the instant BRIEF DESCRIPTION OF THE DRAWINGS The FIGURE is a-schematic view showing of a preferred embodiment ofthe invention.

DETAILED DESCRIPTION OF THE INVENTION In the FIGURE a roll of Stock 11, such as paper, is mounted on a Spindle 12 which rotates about a Shaft 13. It is necessary that the Paper 11 be easily applied to and removed from the Spindle l2 and therefore. ordinarily the Spindle l2 and Paper 11 are free to rotate with respect to one another. A cam mechanism is used to provide tension between Paper and Spindle 12 so that they rotate simultaneously. The cam mechanism includes a" Belt passing around Spindle 12, a fixed Shaft 16, and a Biasing Post 17 which is positioned between Shaft 16 and Spindle .12. Post 17 is mounted on a Follower 18 which is rotatably mounted about the axis of Shaft 16. Accordingly, rotation of Follower 18 about the axis displaces Biasing Post 17 resulting in the application of a force against Belt 14, thus increasing the tension in Belt 14 and providing a'snug fit around Spindle 12 restricting the Paper 11 and Spindle 12 from rotating freely. Displacementof Biasing Post 17 in the opposite direction relieves tension in Belt 14 and Paper 11 and'Spindle 12 can then rotate freely. It should be noted-that because Follower l8 and Shaft 16 both rotate about the same axis. movement of the Follower 18 does not displace Idler 16. Movement of Follower 18 is caused by a Cam 23, as explained hereinafter.

A Leverl9 is rotatably mounted about a Pivot Axis 21. Fixedly attached-to Lever 19 is a Carrier Plate 22 upon which is mounted a Cam 23. Pivot Axis 21 serves as the rotational axis for bothLever l9 and Cam 23 and Follower 18 is biased against Cam 23 by a Spring 38. Accordingly. as Lever 19 rotates about Axis 2], Cam 23 also rotates and Follower 18 is physically displaced so that Biasing Post 17 either applies or removes pressure to Belt 14 depending upon the direction of rotation. Fixedly attached to the other end of Lever I9 is another Carrier Plate 24 upon which is rotatably mounted another Idler 26.

Paper 11, or other material, passes over ldler 26, over another ldler 27 which is rotatably mounted to the cabinet, a portion of which is indicated by reference number 30, of the mechanism in which the invention is utilized. The Paper 11 is pulled by a Driver Roller 25 and onto a Storage Roller 28. Motors, notv shown, of convenient types and sizes are utilized to cause rotation of Driver Roller 25 andStora'ge Roller 28. Rotation of Driver Roller 25 pulls the Stock from Supply 11 as indicated by the arrows. The pullin'g'of thepaper applies tension to the paper and causes Lever'19 to be pulled counterclockwise for the arrangement shown in the FIGURE. This force acts against the biasing force applied to Lever 19 by Spring 37 which is arranged'to cause Lever 19 to rotate clockwise for the arrangement shown in the FIGURE.

A Microswitch 29 is mounted in the proximity of Carrier 22 of Lever 19. Associated with Microswitch 29 is a resilient Wiper or Follower 31. lnterposed Wiper 31 and Microswitch 29. is a Switch-actuating Button 32. When Follower 31 depresses Button 32, the Microswitch 29.changes from a normallyclosed condition to an open condition.

The end of Carrier 22 in the proximity of Follower 31 is configured to have twoswitching or Land Areas 33 and 34 with a Valley 36 interposed the twolands. Normally, Wiper 31 will rest in the Valley 36 and Microswitch 29 is closed. However, when Follower 31 rests upon either of Lands 33 or 34, Button 32 is-depressed and Microswitch 29 is open. Because Follower 31 is made of a resilient material, a natural following of the contour of Carrier 22 results and Microswitch 29 is responsive to movement of Lever 19.

The operation of the invention can be best understood by first assuming that the driver motors are in the OFF position. In this condition, no pulling force is applied to Carrier 24 of Lever 19 and the Lever is in the rest position. in the rest position Follower 18 rests against Cam 23 because of the pulling force of Spring 37 and Biasing Post 17 is slightly to the right so that tension is applied to Belt. in this position Paper 11 and Spindle 12 are restricted from rotating. When the Motor is turned on, Driver Roller 25 beginsrotatin g' creating tension in the Stock and applying a force to Carrier 24 through ldler 26 resulting in Lever 19 rotating slightly counterclockwise because of rotation about Axis 21. The rotation of Lever 19 and Carrier 22 about Axis 21 causes Cam 23 to rotate. Cam 23 is arranged with respect to Axis 21 so that counterclockwise rotation of Lever l9 resultsin clockwise rotation of Follower 18, and vice versa. Accordingly, the counterclockwise rotation of Lever 19 moves Follower 18 clockwise about the axis of Shaft 16 thereby slightly moving Biasing Post 17 from between Shaft 16 and Spindle 12, decreasing the tension in Belt 14. Paper Stock 11 and Spindle 12 are then free to rotate simultaneously. When the Motor driving Driver Roller is turned off, Lever 19 returns toward the natural rest position inherently increasing the tension in Belt 14, thereby preventing the continued rotation of the Paper and thus eliminating backlash of the paper.

When the supply of paper is exhausted and no longer passes over ldler 26, the pulling force is removed from Lever 19. Spring 37 then causes Lever 19 to rotate in a clockwise direction about Axis 21. Carrier 22 rotates along with Lever 19 and Follower 31 rides onto Land 34 depressing Button 32 to open Microswitch 29 and cause, the driving motors to be turned off. In the event that excessive tension is applied to ldler 26 of Lever 19 5 because of the jamming of the pulled Stock, Lever 19 rotates counterclockwise and Follower 31 of Microswitch 29 rides onto Land 33, depressing Button 32 and opening Switch'29 to shut off the driving motors and preventing tearing the Stock or damaging the system. invention therefore 'uniquely'provides tension between. the Stock being fed and Carrier Roller 12 to prevent undesirable backlash, and also automatically deenergizes the feed mechanism when the Stock is exhausted or when excessive tension is applied to the Stock because of some malfunction within the system.

We claim:

1. A device for controlling-thefeeding of rolled material in a feeding mechanism including means for applying a force to said material. and having a supply spindle and a storage roller comprising:

a lever-pivotably mounted in the proximity of said supply roller; cam means fixedly mounted on said lever so that said lever and said cam means rotate in unison;

follower means pivotably mounted in the proximity of said cam means, said follower means being biased against said cam means so that rotation of said cam means causes rotationof said follower means;

means responsive to rotation of said follower means for applying and removing tension to said supply roller as said follower rotates in different directions;

switch actuating means arranged for rotation with said lever, said switch actuating means being configured to include two switching areas;

switch means in the proximity of said switch actuat ing means, wiper means for changing the condition of said switch, said wiper means being biased against said switch actuating means and causing the condition of said switch means to change upon reaching either of said switching areas; and

idler means rotatably mounted on said lever, the

rolled material passing over said idler means to apply a rotating force to said lever so that said wiper means normally rests between said switching areas and rests on one of said switching areas when said force increases in response to forming of said material-and the other of said switching areas when said material is exhausted.

2. The device of claim 1 wherein said means for applying and removing tension includes:

guide means fixedly associated with said follower means, said guide means being located at the pivot axisof said follower means;

biasing means interposed saidguide means and said supply spindle, said biasing means being carried by said follower meansso that movement of said follower means and causes displacement of said biasing means;

belt means passing over said supply spindle, said guide means, and said biasing means so that movement of said follower means in opposite directions respectively increases and decreases tension in said belt means. i i i i 

1. A device for controlling the feeding of rolled material in a feeding mechanism including means for applying a force to said material and having a supply spindle and a storage roller comprising: a lever pivotably mounted in the proximity of said supply roller; cam means fixedly mounted on said lever so that said lever and said cam means rotate in unison; follower means pivotably mounted in the proximity of said cam means, said follower means being biased against said cam means so that rotation of said cam means causes rotation of said follower means; means responsive to rotation of said follower means for applying and removing tension to said supply roller as said follower rotates in different directions; switch actuating means arranged for rotation with said lever, said switch actuating means being configured to include two switching areas; switch means in the proximity of said switch actuating means, wiper means for changing the condition of said switch, said wiper means being biased against said switch actuating means and causing the condition of said switch means to change upon reaching either of said switching areas; and idler means rotatably mounted on said lever, the rolled material passing over said idler means to apply a rotating force to said lever so that said wiper means normally rests between said switching areas and rests on one of said switching areas when said force increases in response to forming of said material and the other of said switching areas when said material is exhausted.
 2. The device of claim 1 wherein said means for applying and removing tension includes: guide means fixedly associated with said follower means, said guide means being located at the pivot axis of said follower means; biasing means interposed said guide means and said supply spindle, said biasing means being carried by said follower means so that movement of said follower means and causes displacement of said biasing means; belt means passing over said supply spindle, said guide means, and said biasing means so that movement of said follower means in opposite directions respectively increases and decreases tension in said belt means. 